Re: RPG on a Windows (Techncial Discussion...)

(I changed the subject a bit here, since I don't want to give the impression
that I am trolling or anything like that. But I do love good conversation! :)
At my day job, we had to write an indexed file system similar to VSAM for a
Linux platform. I know I know, there are some out there already, but... we just
didn't like 'em. :)
Anyway, the point is, that is almost exactly how we handle record locking. We
have a table of all the records that have been "locked", but we did not
physcially lock the file in any way. Only when the the actual write request
comes through do we physically lock the record. It is fast, clean, and once we
figured out how to use the correct signals to keep the in-memory tables clean
(and how to use shared memory and semaphores and so forth... :) it works
perfectly. Of course, optimistic locking is pretty darn trivial this way,
though we do have to store the "pristine" copy of the record in application
memory space. And it is fast. So it is definately possible.
That's without using a database of course. I'm fairly confident that doing the
same thing on an Intel Linux system would be pretty easy, though it would have
to be written. The implementation we did is in HLASM for the zSeries platform.
;)
-Paul